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Super Volcano about to explode? .... "Lake Toba" ... MEGA DOOOOM ???
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Is a massive volcanic eruption from Lake Toba in Indonesia immanent?.
Image of location below ...
[link to upload.wikimedia.org]
(less than 50% of article)
Lake Toba is a lake and supervolcano. It is the largest lake in Indonesia and the largest volcanic lake in the world. Lake Toba is the site of a supervolcanic eruption that occurred an estimated 69,000 to 77,000 years ago, a massive, climate-changing event. It is estimated to have been a VEI 8 eruption. It is the largest known explosive eruption anywhere on Earth in the last 25 million years. it has been accepted that the eruption of Toba led to a volcanic winter with a worldwide decline in temperatures between 3 to 5 °C (5 to 9 °F), and up to 15 °C (27.0 °F) in higher latitudes.
The eruption was large enough to have deposited an ash layer approximately 15 cm (5.9 in) thick over the entire South Asia; at one site in central India, the Toba ash layer today is up to 6 m (20 ft) thick and parts of Malaysia were covered with 9 m (30 ft) of ashfall. In addition it has been variously calculated that 10,000 million tonnes (1.1×1010 short tons) of sulphuric acid or 6,000 million tonnes (6.6×109 short tons) of sulphur dioxide were ejected into the atmosphere by the event, causing acid rain fallout.
The Toba caldera is the only supervolcano in existence that can be described as Yellowstone's "bigger" sister.
The subsequent collapse formed a caldera that, after filling with water, created Lake Toba. The island in the center of the lake is formed by a resurgent dome.
More recent activity
Smaller eruptions have occurred at Toba since. The small cone of Pusukbukit has formed on the southwestern margin of the caldera and lava domes. The most recent eruption may have been at Tandukbenua on the northwestern caldera edge, since the present lack of vegetation could be due to an eruption within the last few hundred years.
Some parts of the caldera have experienced uplift due to partial refilling of the magma chamber, for example pushing Samosir Island and the Uluan Peninsula above the surface of the lake. The lake sediments on Samosir Island show that it has been uplifted by at least 450 m (1,476 ft) since the cataclysmic eruption. Such uplifts are common in very large calderas, apparently due to the upward pressure of unerupted magma. Toba is probably the largest resurgent caldera on Earth. Large earthquakes have occurred in the vicinity of the volcano more recently, notably in 1987 along the southern shore of the lake at a depth of 11 km (6.8 mi).
Lake Toba lies near the Great Sumatran fault which runs along the centre of Sumatra in the Sumatra Fracture Zone.[9] The volcanoes of Sumatra and Java are part of the Sunda Arc, a result of the northeasterly movement of the Indo-Australian Plate which is sliding under the eastward-moving Eurasian Plate. The subduction zone in this area is very active: the seabed near the west coast of Sumatra has had several major earthquakes since 1995, including the 9.1 2004 Indian Ocean Earthquake and the 8.7 2005 Sumatra earthquake, the epicenters of which were around 300 km (190 mi) from Toba.
On 12 September 2007, a magnitude 8.5 earthquake shook the ground in Sumatra and was felt in the Indonesian capital, Jakarta. The epicenter for this earthquake was not as close as the previous two earthquakes, but it was in the same vicinity.
On 26 October 2010, a magnitude 7.7 earthquake occurred 36 kilometers (22 mi) southwest of the nearby island of Pagai-selatan. A 3-metre (10 ft) tsunami immediately followed the quake.
On 10 January 2012, a magnitude 7.3 earthquake occurred within the area.
The 2004 earthquake physically rolled the Sumatran island and altered the shape of the Earth as was detected by the GRACE satellite. Recent highly localized earthquake activity may initiate magmatic activity of this colossal global climate modifier.
[link to en.wikipedia.org]
Indonesia Earthquake (Magnitude 8.6) Wednesday 11th April 2012
A great earthquake (magnitude 8.6) hit off the coast of Aceh, Indonesia on 11th April 2012. The epicentre was 434 km SW of Banda Aceh, and the focus was at a depth of 22 km. A tsunami warning was issued for countries surrounding the Indian Ocean. Earthquakes of this magnitude have the potential to affect volcanoes within a 700 km radius. This includes Toba. A magnitude 8.2 aftershock occurred 2 hours after the great earthquake.
[link to www.volcanolive.com]
Here is a good image of the bigger quakes and how close they were to Toba.
[link to www.emsc-csem.org]
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